Fair Value Measures and Disclosures (Tables)

9 Months Ended

Sep. 30, 2020

Fair Value Disclosures [Abstract]

Fair Value, by Balance Sheet Grouping [Table Text Block]

The following table summarizes the fair value of the Corporation's financial instruments at September 30, 2020 and December 31, 2019:

Fair Value of Financial Instruments	Sep 30, 2020								Dec 31, 2019
In millions	Cost		Gain		Loss		Fair Value		Cost		Gain		Loss		Fair Value
Cash equivalents 1	$	10	$	—	$	—	$	10	$	10	$	—	$	—	$	10
Long-term debt including debt due within one year	$	(391)	$	—	$	(95)	$	(486)	$	(474)	$	—	$	(115)	$	(589)

1.Money market fund is included in "Cash and cash equivalents" in the consolidated balance sheets and held at amortized cost, which approximates fair value.